This invention relates generally to shaft sealing devices protecting bearings for use with rotating equipment. Adequate maintenance of rotating equipment is difficult to obtain because of extreme equipment duty cycles, the lessening of service factors, design and the lack of spare rotating equipment in many processing plants.
Various forms of shaft sealing devices have been utilized to try to protect the integrity of the bearing environment including rubber lip seals, clearance labyrinth seals, and attraction magnetic seals. Lip seals or O-ring shaft seals can quickly wear out and fail and also permit excessive amounts of moisture and other contaminants into the oil reservoir of the operating equipment even before failure.
Labyrinth-type seals involving closely related stator and rotor rings, which do not contact each other but define labyrinth passages between them have been devised and utilized and are illustrated in Orlowski, U.S. Pat. Nos. 4,706,968; 4,989,883; 5,069,461; and the additional patents to Orlowski cited therein. As described in Orlowski U.S. Pat. Nos. 4,989,883 and 5,069,461, improvements in labyrinth seals are disclosed including the utilization of various forms of O-ring seals to improve the static sealing action when the shaft is at rest and non-contact dynamic sealing action when the shaft is rotating.
The seal was improved by the insertion of an O-ring seal inserted into a female cavity. The cavity was in both the rotor and stator and the O-ring was inserted in a novel way by deforming the resilient seal as it was forced into the cavity. Once in position i.e., in the female cavities, the seal returns to its original shape and rotated with the rotor. In addition it secured the rotor and stator together to prevent axial separation of the rotor and stator while static.